Piston for explosive-engines.



Nb. 668M175. v Patented Feb. l2, I90l.

W. 0. WORTH.

PISTON FOR EXPLUSIVE ENGINES.

(Application filed Apr 9, 1900.) (No Model.) 3 Sheets-Shea1 l.-

n1: News PETERS co, vumaumow WASHINGTON, 04::

INu. mwm. Patented Feb. l2, 190i.

W. U. WORTH.

PISTUN F08 EXPLOSIVE ENGINEQ.

(Application filed Apr. 9, 1900.) (W o- M o d 81.)

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i Z I 3 Sheets-Sheet 3.

Patented Feb. 12, l90l.

W. 0. WORTH.

PISTON FOB EXPLOSIVE ENGINES.

(Application filed Apr. 9, 1900.]

lNo. 668,075.

(No Model.)

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'WlljliIAlll O. "WORTH, OF CHICAGO, ILLINOIS, ASSIGNOR OF TWO-THIRDS TOIVIIJIJIAM R. DONALDSON, OF SAME PLACE, AND HENRY W. KELLOGG,

CF BATTLE CREEK, MICHIGAN.

lF lSTUbl FUR EMPLOSWIE ENGBNES.

SPECIFICATION forming part of Letters Patent No. 668,075, dated February12, 1901.

Original application filed September 9, 1899, Serial No. 729,910.Divided and this application filed April 9, 1900. Serial No.

To all whom, it iii/(by concern.-

Be it known that l, WILLIAM O. WORTH, a citizen of the United States,residing in Chicago, county of Cook, and State of Illinois,

have invented certain new and useful Improvements in Pistons forExplosive or Rapid- Combustion Engines, (being a divided applicationfrom the original filed September 9, 1899, Serial No. 729,910;) and I dohereby to declare the following to be a full, clear, and exactdescription, such as will enable persons skilled in the art to which itappertains to make and use the same.

My invention relates to improvements in i5 pistons for explosive orrapid-combustion engines or to engines of any class where the power isapplied to the piston by sudden intermittent impulses, as when theabruptive impact is applied to a reciprocating piston by so theexplosion of a charge of gas, vapor, or other material that may be usedthe nature of which is to impart its energy in impulses of great initialforce, but of short duration. v

The object of my invention is to provide a piston that will absorb aportion of the energy liberated by a charge of fuel having thecharacteristics described and which will contribute the power or forceso held in reserve by the said piston to the other moving parts 0 of theengine at a time later in the stroke, when the direct effect of theexploding charge has been diminished.

The force of an exploding charge within the cylinder of an ordinaryengine of the class described is so violent and comes with such suddenvigor that the effect upon the mechanism of the engine is similar to theresults that would follow from the concussion produced by sledge-hammerblows of equal on 4.0 ergy.

This improved piston may be made a part of the ordinary reciprocatingpiston, or it may be an independent auxiliary piston that may beadjusted so as to enlarge the contents of the cylinder at the time ofthe severest effect of the explosion and then by returning to its formercondition in virtue of the compressed resilient element associatedtherewith reduce the contents of the cylinder to'its normal ca- (Nomodel.)

pacity, and therebyimpart to the moving piston the energy that will bestored in the said element, which is compressed by the said auxiliarypiston at the instant of the explosion.

In the drawings, Figure 1 is a plan View of an engine containing myimproved pistons attached and a part of the ordinary piston. Fig. 2 is aside elevation of the same. Fig.

3 is an enlarged broken-away portion of the view shown in Fig. 1 insection, showing the pressure-valve located in my improved piston, alsothe auxiliary piston located in the side of the cylinder. Fig. 4: is anenlarged detailed sectional view of the piston pressu revalve. Fig. 5 isa section of same through lines 5 5 of Fig. 4. 55

In all of the views like letters of reference are used to indicatesimilar parts.

The pistons b b are connected to. their respective cranks by the usualconnecting-rods b and b By referring to Fig. 3 it will be seen that thepistons are composed of two major portions-the outside shell U, whichcarries the usual packing-rings, and an internal piston 79, which alsocarries a series of packii1g-rings W. The latter is adapted to bereciprocated within the former. b carries a pin b upon which thecrank-arm b has bearing. A series of open spiral springs b" 19 aredesigned to hold the component parts of the piston in 80 the positionnormally occupied and as shown in Fig. 3. The head of the piston b isperforated by a small hole, preferably near its center, into which avalve b is seated by spring Z). The power of this spring is proportionedto the area of the valve and is sufficient to hold the valve closedagainst a pre determined pressure within the cylinder Ct.

Referring to Figs. t and 5, ring I) (shown only in Fig. 5) extends fromthe outer surface of the main piston-head and is formed into an annularexterior-threaded projection. A sheet spring or flexible diaphragm b isplaced over the face of the projecting ring h and the cap Z1 is thenscrewed on, and by 5 this means the diaphragm Z9 is firmly securedaround its edges, leaving its center free to be moved by the pressure,as will be 'ring 19 and cap 5 and at a point opposite to that at whichit is connected to the diaphragm a recess or guide 19 is formed in itfor the valve-stein of the valve b. The valve-closing spring Z7 has oneof its abutting ends resting against the yoke. An airvent or passage-wayb opening into chamber b", communicates with the outside atmosphere orwith the com pression-chamber A, as may be desired. The spring b abutsagainst the surface of the cylinder a and the yoke Z1 and holds the saidyoke normally in the position shown. This spring is auxiliary to thespring 19 and diaphragm Z9 and is not absolutely essential.

The internal space between the pistons and b I will call thepressure-space, and designate it by 5 The object of this space is tomaintain a constant quantity of air or fluid between the two pistons asan auxiliary for the springs 19 b or in lieu of any springs, and theobject of the valve Z7 and its associated elements is to prevent thisquantity from falling below a desired value, or rather GeV the office ofthe valve referred to is to supply the quantity that may be lost byleakage or otherwise from time to time, so that the cushion thusproduced may be relied upon to perform in a constantdegree the functionsfor which it is intended.

In Fig. 2 only open spiral springs are shown for the purpose of holdingthe two portions of the piston 17 and b in a strained relation in lieuof-the air-cushion just referred to. In this event the valve andappurtenant elements just described are not essential.

In Fig. 3 an auxiliary cylinder e is shown, made into the side of thecylinder at, preferably within the combustion -'space or at a placewhere the piston 19 will not cover it at the time when the explosiontakes place. A piston 11 is adapted to be reciprocated within thecylinder a Spring 71 holds the piston in the position shown. Anair-valve and aircushion may be used instead of the springs 12 such asare shown in connection with piston 11 and in detail in Figs. stand 5.The piston 19 is cushioned by the elastic medium pent up within theannular space a, provided within the cylinder a A similar space Z9 andfor the same purpose is provided in piston b It is of great importancefor the continuous smooth operation of an engine that the variouscharges of mixture, regardless of quansprings, compressed air, or both.In Fig. 2 springs only are shown. In Fig 3 I have shown springs 19* andb and also a means for admitting compressed air or gas between the twoparts of the piston for accomplishing the same result. When the tensionbetween the two parts of the piston is greater than the compressionwithin the cylinder at, the piston will move ahead bodily as one piece;but when the two pressures begin to approach equality the part 5*, ofwhich Z2 is the head, Will practically remain stationary and the part bwill move ahead and by this action will further compress the springs 19b and the air contained within the chamber b and then b will move aheadagain until another equilibrium has been established between the twopressures.

The admission of gases within chamber Z2 from cylinder at in virtue ofthe momentarilyincreased pressure of the explosion cannot pass beyond apredetermined limit at any 7 time, and any lack in quantity is securedby operation of the valve b in the cylinder-head b The valve Z2 isseated normally by an open spiral spring Z9 The extended end of thevalve is guided in yoke-piece Z7 and this yoke-piece is attached at Z7to diaphragm b, which covers a chamber 1)", that is open to theatmosphere by the duct When the airpressure within the chamber Z9 risesabove a certain determined point, the diaphragm Z2 is pressed inwardtoward the cavity Z9 in virtue of the difference of pressure existing onthe two sides of the diaphragm 19 and the yoke 17 which is attached tothe diaphragm and which bears against and supports valve b presses valveo more firmly onto its seat and prevents the further admission of gaswithin the chamber Z9 Should the pressure'within the chamber 12 fallbelow the normal or predetermined point, the pressure on the diaphragmZ9 would be less from within, and the valve 1) would therefore be lessfirmly held in its seat, and in consequence the deficient quantity ofgas necessary to raise the pressure within the chamber 19 would beadmitted through valve 1) from the cylinderawhen the pressure thereinhas been raised to its maximum degree. The power consumed in compressingthe air or springs within the chamber Z9 of the piston is held in astored condition and is given back to the return stroke, so that thereis no lost energy as a result of this operation. When the charge isfired in the manner set forth, the violence of the abrupt explosion isabsorbed to some degree by the effect of compressing air or the springswithin the piston. The power thus stored is given out at alater part ofthe stroke, and thus the impulse occasioned by the explosion is impartedto the moving elements of my engine by a more gradual and prolongedpressure. A greater portion of the resulting energy is converted intomotion instead of heat, because the yielding parts may at once respondinstead eeaovs of requiring the inertia to be overcome before the energycan betransformed into motion. The yielding piston also serves as acushion and relieves the mechanical organism from sufferingbythepercnssiveviolence of the explosion. The result of thisconstruction is that the explosion is relieved of its violent initialimpact, and thereby the effect of the impulse is distributed over agreater part of the stroke. The extreme pressure within the cylinder tooccasioned by the violence of the explosion therein will cause thepiston Z9 to be driven deep into its cylinder 0. against the resistanceof the springs b or compressed air or gas, should that form of piston beused, the effect of which is to enlarge the contents of the cylinder aand to modify to some extent the high pressure effected by theexplosion. As the piston 17 leaves the cylinder at in completing thestroke the resilience of the -springs b will cause the piston U toreturn to its nornial position, therebydecreasing the contents of thecylinder 0., and as a result an even constant pressure is maintainedwithin the cylinder a during a considerable portion of the stroke, whichrenders the engine highly economical.

Another benefit to be derived from this construction is that which hasalready been referred to, to wit: The fierce and violent concussion isnot imparted to the working parts of the engine; but a portion thereofis absorbed by the most sensitive expansible pistons, and th us a steadyeven motion is imparted to the moving portions of my engine. The workingparts and the frame of the engine may be made lighter, as the strainthereon is not so great when the power is applied in steady evenreciprocations of even constant pressure as when the impulses come insharp high-pressu re impacts of short duration.

1 do not desire to be limited to the exact constructions shown anddescribed, but de sire to avail myself of the right to make such changesin the form and arrangement of the various parts of the apparatus asfairly fall within the spirit and scope of my invention;

Having described my invention, what I claim as new, and desire to secureby Letters Patent of the United States, is-

1. An engine of the class described, comprising a main shaft, acylinder, a composite piston, an air-chamber between the parts of thesaid piston, a valve-opening, between the cylinder and the said chamber,a valve for said opening and a means responsive to the pressure withinthe chamber for holding said valve on its seat, substantially as setforth.

2. An engine of the class described, comprising a main shaft, acylinder, a composite piston, an air-chamber between the parts of thesaid piston, an opening from said chamher, and a diaphragm covering saidopening, adapted to operate a valve, substantially as set forth.

3. An engine of the class described, comprising a main shaft, acylinder, a composite piston, an air-chamber between the parts of thesaid piston, a valve-opening communicating between said cylinder andchamber, a valve held in its seatby a diaphragm within said chamber,said diaphragm being made responsive to a difference of pressure betweenthat of said chamber and that of outside atmosphere, substantially asset forth.

4. An engine of the class described, comprising a main shaft, acylinder, a composite piston, an air-chamber between the parts of saidpiston, a valve-opening, communicating between said cylinder andchamber, an airpressure responsive device within said chamber forholding said valve closed when the pressure within said chamber reachesa predetermined value, substantially as set forth.

In testimony whereof I have signed this specification, in the presenceof two subscribing witnesses, this 4th day of April, 1900.

NILLIAM O. WORTH.

\Vitn esses:

Eonitn BAIN, M. F. ALLEN.

